Telephone-exchange system.



,maires sinies rainer enrichi;

enemies L. GooDnUM, or Nnw YORK, N. Y.,'AsS1eNoR, BY Miisi'vn ASSIGNMENTS, To WESTERN ELECTRIC COMPANY, INCORPORATED, A conroiiATioN orNEw YonKq,

' rniiiiriioNE-,EXCHANGE SYSTEM.

meinen Application led December 12,1914. Serial No. 87.63338. Y

To allai/1,0m zzmay/ concern Be it known that I, CHARLES Ii. GooDiiUM,

a citizen of the United States, residing at New York, in the county' lof Newv York and vState of New York,have invented certain new and'useful 'Improvements in Telephone- Exchange Systems, of which the following is a full, clear, concise, and exactdescription.

This invention relates to a telephone exchange system, and its object is to provide" means by which, when a--Subscribers tele,-

phone number is changed, connection withv his telephone can be secured b y calling either the old or the new number. Vhile theinvention is applicable in general to achange in a Subscribers telephone number, it is especially applicable where` there is also a change inthe kind of service.

Witlrthe' above object in view, and in accordance with the invention, a special Switch I is connected to the connector multiple terminals of the old number and operates, when connectionl is made to those terminals", to

`automatically extend the connection to the new line. In 'case there is n0 change in the kind of service, the Special switch would merely step to a terminal to which thenew line is connected. In case there is a change in the kind of Service, as, for exam-ple, from an individual line to private branch eX- change trunks, the. special switch, which is..

connected 4to the connector multipleterminals of the old number, operates, when connection is made to thosel terminals, to test over and hunt for an idle one of the private branch vexchange trunks. The private branch exchange trunks or the new line, as

the case may be, are valso connected to their 40 y proper new number terminals on the connectors, so -that service is secured either by calling the new or the old number.

As an additional feature of the invention,

a message register may be providedfor counting the calls that come through the old number terminals, the purpose being to keep the'special switch in 'that particular servicel only until the other vsubscribers become familiar 'with the new number, which factA is disclosed by the message register.

The invention may be more readily .funder- 'I'stood by reference 'to the accompanying .ing of well-known type and drawing, showing an arrangement lof circuits andv apparatus embodying the invntion.

In the drawings,the Subscribers telephone station A is shown as served a plurality of private branch exchange trunksl, 2, 3. At the main office these trunksareconnected to the multiple terminals of .a trunk hunting connector B. Itis assumed tli'athe Subratenteii oet, "i7, icio. 5 i

scriber' formerly was served byanaindi-.

vi'dual line' connected to multiple"terminals on a connector C, and that the service ing been changed from an individual line to privatev branch exchange serv-ice, a new number given to the subscribers station. In order that thel subscriber'f-may-be readily reached even if the old number Ais cal-led,-

Therefore when a calling line is connected tol the terminals of the connector V'C, the` trunkhunting switch D hunts for an idle trunk leading-to the subScribeNs'station A.. The apparatus may. be of any suitable conf struction, that indicatedin the-drawing be-v hence shown in a conventional manner.

The operation of the system is as follows: In case a call is made for the subscriber at station A and the call is for his new ninn-v ber the trunkhunting connector .connects the calling subscriber with the ,private branch exchange of the wanted subscriberlin the usual manner. If, however,- the eall is' made for the old instead of the new. nulli: vber, the calling subscribers linei's extended in the usual manner to-'the'multiple,trminals 4,'5 of the"connector C to which the wanted y subscribers line was formerly` .directly connected. 1 Thereupon a' circuit is from grounded battery, through one I,winding of relay 9, noi-mal contact 10, closedn the initial position o fswitch 1D, contact y8 Aclosed over the local third wire for the relay 6, which being actuated opens its back clon-` tact 7 and closes 'its front Contact 8, thereby l .l closing a-'circuit for a relay 9 as followsz; f

grounded battery, l through the other winding of relay 9, front contact 11 o'frelay 9, side switch 12 and brush 13 of's'witch 'i'to ground. Relay 9' controls, at its front Contact 14, ia circuit for -the motor magnet.

- l and the escape magnet 16 ofswitch D.

' '-cuit at contact '17, thereby advancing the. stepby ,1Q

...terminals of the idle trunk,

magnet-16 causes the side switches 20, 21 and-,12to move to their second position. IIn

i ilected trunk busy. Thel brushes 20 and 21 The motor magnet-1 5 interruptsits own cirsuch position the brush l2 connects the brush13f-to ground, thereby making the se-A connect the vcalling line to the brushesu18 lected private branch 'exchange trunk. The

' calling subscribers lineis thus connected ,to the private branchl exchange, and-connecl` i rj'ti'on with. a subscribers -telephone setat that exchange -can be made in any usual or suitable manner.

i ,-contactf y thereby completing `a'circuit for release magnet 23 as follows; from ground'- f-norinal. Means are .provided whereby i f subscriber, instead of having ed battery, through release magnet' 2 3, olinormaleontact 22, closed in the, operated positionvof switch D, contact 7, to ground..

'I he special switch D isthus restored to.

allthe private branch exchange trunks are busy,xa busy tone is sent'back to the calling subscriber. i ing'- tested 'thejtrunk terminals and having found them all -busy, move ajstep. farther so that brush 1 8 is connected with the busy tone apparatus 2.4. .It is obvious that if a .had "a single old number, had had two or more numbers,

f --the .special switches he can still be reached by callingany one of the'old -numbers by'merely duplicating of the. trunks 1, 2,V 3, to terminals on each of the'switches' D. In such case the -conductors25 would extend to the terminals offrone oflsuchadditional switches. D and- ,f-th'e pairfof conductors -2G'to the'terminals o f still anther such switch.l The .special switcl1 D,' is preferably provided with an additional side switch arm' 27 ,arranged in i electromagnet"28; .Each 'time themagnet 28 its'sec'ond position to close aj'circui-t for. an

"isfenergized it'attracts its armature 29 and actuates a ratchet 30 of a register Wheel 81.

lfhevregister thus makes one count each time4 We switch Dv is 'used. By thusnindicating subscriberfs old. number, A

trunk-hunting switch connected to said old number terminals and having terminals to -which said private branch exchange trunks vWhen the subscriberv calling` the old numbervhangs up his telephone the relay 6 is denergized andj closes itscbackv System nals representing -a subscribers old number,

.Insuch case the brushes, havel) and extend-i ng each how frequently the old-number is called, it can be determined when the new number has been generally adopted by the other subscribers ofthe system, 'and hence when the usebf 'the special switch may be discontinued.

' What'is claimed is:

1. In atelephone system,'terminals representiiig a subscribers old number, terminals representing said subscribers iie\\"iiuiiiber,

aline connecting said new number terminals v to the subscribers station, and an automatically operating switch for extending aconnection from said old number terminals to said line. v

2. In a telephone system, teriiiina'ls represent-ing a subscribers old number, terminals representingsaidsubscribers new number, a lineconiiecting said new number termi- .nals to the subscriber-s station, and an. automatic switch 'connected to said old number terminals and having terminals ,connected to said line.

3.1In' a telephonesystem, terminals rep-V i'esenting ,a subscribers new number, pri- .vatejbranch exchange trunks connected to said terminals, terminalsrepresenting said are connected.

4. Inan j automatic-telephone exchange a connector having multiple termia connectorhaving multiple terminals representing said subscribers new number, a

line connecting `said new number terminalsto" :the subscribers station, andan automatic switch connected to said old number termi nalsand having terminals connected to said line.

nals representing a s ubscribefs old, .discontiiiued, individual line number, connectors having multiple terminals representing saidA subscribers new numbers, private branch exchange.trunksconnected to said connectors, and an automatic trunk-hunting-switch connected to saidold number terminals and having terminals 'tot which said private branch exchange t'runks are connected.

G. In a telephone system, terminals representing si'ibscribers new. number, private branch vexchange trunks' connected to said terminals, terminals representing said subscribers'old number, a hunting switch for extending a connection from said old number terminals to terminals of an idle one of said trunks, and a register responsive-to the operation of Silid switch.

7 Ina .telephone system, a telephone line,

'means including automatic switches for extending a connection to said line, terminals 5. In anautomatic telephone exchange system, a connector having 'multiple termi-l and an automatic ing connected to certain of said terminals,

at said switches representing different line my name this 11th dayo Decembe; numbers or" said line, said telephone line be- 1914. f

and an electrically controlled switching de- CHARLES L GOODRUMX 5 vice for joining other' terminals to said tele- Witnesses:

phone hne. E. EDLER,

In Wltness whereof, I hereunto snbscrlbe K. L. STAHL. 

